Macintosh SE Video Issue (single vertical line)

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Macintosh SE Video Issue (single vertical line)

I'm having an issue with my Mac SE where the video goes to a single vertical line (1 pixel thick) after about 20 minutes of use. If I turn it off, and wait about 5 seconds, it comes back, but I really don't like switching it off like that (as it's really not good for the power supply). The analog board looks good, but I don't have the proper equipment to check the capacitors. Does anyone know what's going on? Is it the capacitors? And if so, does anyone have a list of the replacements I'm going to need?

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Bad connectors.

Bad connectors.
Check the contacts between the digital and the analog boards.

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Check C15 and the yoke connector

Most likely it's C15, the 3.9uF NON-POLARIZED cap. You should also check the yoke connector P1; those pins often develop cracks where soldered.

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jeffmazur wrote:Most likely

Most likely it's C15, the 3.9uF NON-POLARIZED cap. You should also check the yoke connector P1; those pins often develop cracks where soldered.

Is it possible for you to post a picture of the component so I know where, and what I'm looking for? I'm still really new at this.

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Here you go
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OK, so I've been trying to

OK, so I've been trying to find a suitable replacement cap, but I'm having no luck. Anyone know where I can get one? Also, what's the voltage? I have three SE's and they're all brown and unmarked.

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The original is 35V but

The original is 35V but higher is always better. If you want to confirm that's the problem and you have some spare caps, try temporarily replacing with two 4.7uF 35V (or more) caps wired in series back to back (i.e. positive of one connected to positive of other). If that proves to be the issue, you can find the correct part easily on ebay. Just search for 3.9uf NP. There's at least one item on there now that has 2 caps for less that $10.

And you have three SE's with unmarked caps? They don't look like the one in my pic?

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And you have three SE's with

And you have three SE's with unmarked caps? They don't look like the one in my pic?[/quote]

They look exactly like the ones in your picture, except brown and unmarked.

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Did you get this fixed?

Did you fix your problem? I just came across a couple of these caps in my spare parts collection. Let me know if you're still looking for them.

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